Bob Soebijantoro (1986) The Effect Of Storage On The Dimensional Changes of dental stones. Laporan Penelitian. Lembaga Penelitian, Surabaya. (Unpublished)

Bob Soebijantoro (1986) Investigation Into The Accuracy Of Cobalt-Chromium Denture Castings. Laporan Penelitian. Lembaga Penelitian, Surabaya. (Unpublished)